At the end of February, during the testing of complex scientific equipment (KPA) of the satellite "Lomonosov" audited components of the Space Telescope TES. In particular, the staff of Nuclear Physics of Moscow State University, using the stand of "parallel lasers" (photo 1), checked the geometry of the space telescope mirrors TES for defects and stability of the parabolic mirror segments sectors.
Photo 1. Stand parallel lasers
Mirror — one of the most important parts of the telescope TES. It is made on the basis of Fresnel mirror and consists of seven hexagonal segments — one central and 6 of the same side (photo 2).
Photo 2. Central segment side segment
Are arranged in a "daisy" segments are made on the basis of Fresnel mirror and, with its low overall height, provide a concentration of the incident parallel beam of light with a focal length of 1.5 m (3 photos)
Photo 3. Visual inspection mirrors TES for defects
The mirror is designed to work in open space at temperature ranging from -80 ° C to 80 ° C. The stability and permanence of the geometric parameters of mirror in such a large temperature range is achieved by using carbon composites in its construction with zero coefficient of linear expansion.
To achieve the most good reflection mirror in the optical and near-ultraviolet wavelengths as the reflective coating is aluminum of high purity, as well as a protective layer — magnesium fluoride (MgF2). This combination provides the necessary performance and reflecting mirror coating provides protection from atmospheric oxygen.
After checking to protect against accidental exposure to the mirror put on the protective cover (photo 4). Optical surfaces remain protected all the storage and transport of up to final assembly TES on Baikonur. Up to this point protection can only be removed in exceptional cases — for the regulations provided for inspection and testing.
Photo 4. TUS telescope mirror with cover